1. Technical Field
The present invention relates to an image processing device, an imaging device, an image processing method, and a computer readable medium.
2. Background Art
Digital cameras are widely known that are provided with autofocus, in which phase difference detection methods and contrast detection methods are employed, and also what is referred to as a manual focus mode, in which a user can manually perform focus adjustment.
Digital cameras including a manual focus mode are known in which a reflex mirror is provided to enable focus adjustment while checking a subject-image, and a method is utilized in which a split microprism screen is employed to display the phase difference visually. Utilization of a method in which contrast is checked visually is also known.
However, in digital cameras with the reflex mirror omitted that have become prevalent in recent years, since there is no reflex mirror, there is no method to check the subject-image while displaying the phase difference, and contrast detection methods have had to be relied on. However, in such cases, contrast cannot be displayed at a resolution greater than that of a display device, such as a Liquid Crystal Display (LCD), requiring adoption of methods such as enlarging a portion for display.
In recent years, therefore, a split-image is displayed within a live-view image (also referred to as a through image), so as to make the work of focusing on the subject-image easier for an operator when in manual focus mode. Split-image refers to a divided image in which, for example, a display region has been divided into plural sections (such as each image divided in the up-down direction), and in which displacement is imparted in the parallax generation direction (such as the left-right direction) according to focus misalignment, and is a divided image in which the displacement in the parallax generation direction disappears in an in-focus state. The operator (such as a photographer) operates a manual focus ring (hereafter referred to as a “focus ring”) to match the focus so that displacement of the split-image (such as each image divided in the up-down direction) is removed.
In the imaging device described in JP-A No. 2009-147665 (referred to below as “Patent Document 1”), out of light rays from an imaging optical system, a first subject-image and a second subject-image formed by light rays divided by a pupil divider are photoelectrically converted to generate a first image and a second image, respectively. The first and the second images are employed to generate a split-image, and a third subject-image formed by the light rays not divided by the pupil divider is photoelectrically converted to generate a third image. The third image is displayed on a display and the generated split-image is displayed inside the third image, and color data extracted from the third image is applied to the split-image. By applying color data extracted from the third image to the split-image in this way, excellent visibility of the split-image can be achieved.
In the imaging device described in JP-A No. 2011-223562 (referred to below as Patent Document 2), light that has passed through different regions in the left-right direction of an imaging optical system is received, images from left and right viewpoints are acquired by photoelectrical conversion, and shooting correction is performed on the images from left and right viewpoints by applying different shooting correction amounts to the left and right viewpoint images.
In the imaging device described in JP-A No. 2012-75079 (referred to below as Patent Document 3), different shooting correction is applied to left and right viewpoint images that have been captured using a single imaging optical system so as to reduce the brightness difference between the left and right viewpoint images.
The imaging device described in WO 2012/036019 (referred to below as Patent Document 4) includes a two dimensional correction table for correcting shooting with a lens, and a one dimensional correction table for correcting shooting by monocular 3D.